True biennials are only raised from seed as they cannot be raised from other means, such as cuttings.
However, some perennials are best treated as biennials as it is easier to grow them this way, such as Brompton Stocks.
And some of these can be propagated by offsets or division.
Yes, it is confusing. But plants, and nature in general, can be like that sometimes, confusing.
So, to try and make things easier for you all the propagation info is given for each plant listed in freegardeningplants.
The garden, yard, plants that are listed are either true biennials or perennials that are best treated as biennials for the UK climate.
If you live in the USA, Canada or elsewhere you will need to check for your own local growing conditions and zones.
Or contact us for further advice giving us your plant types and hardiness zone, or your location may sometimes do, and we will do our best to give you the details for your zone.
You can propagate all the plants listed quite easily from seed.
Now biennial seeds sown this season will only produce roots and foliage in their first year.
They will not produce any flowers in their first year. But don’t let that put you off growing them as some of the foliage can be attractive and the wait for their flowers is well worth it.
In their second year they will not only produce roots and foliage but they will also produce flowers.
At the end of their second season after the flowers have finished they will produce seeds and the plant will then die.
But as they self seed profusely, there is always a continuation of flowering plants if the seedlings are allowed to grow on.
If you want these self seedlings to grow on where the seeds have dropped and germinated around the plant don’t be too keen to hoe and weed at the end of summer and through into spring as you may kill them off.
Or if you want to grow the seedlings somewhere else in your garden, carefully lift the self seedlings when they are large enough to handle, usually in the spring.
Lift them with your hand fork taking care not to damage the tiny leaves and fine roots.
Lift them altogether in one clump then gently tease them apart, again without damaging the leaves or roots.
Handle them gently and only by their leaves, never by their stems.
Pot them up individually into 7.5cm (3inch) pots filled with a good quality potting compost and place them in your cold frame.
Just grow them on until they are large enough to be planted out in their flowering position. Then just watch them grow, flower, self seed, grow, flower, self seed. It could be endless. More free gardening plants!
Another easy way to propagate these garden plants is to collect the seeds as they ripen.
Sow them in plant cells or seed trays, flats, immediately in a good quality seed and cutting compost and once they have germinated pot them on individually into 7.5cm (3inch) pots.
Over winter them somewhere frost free but cool, a cold frame is ideal.
Harden them off the following spring and plant them out when all frosts have finished. Now that’s real easy!
Unfortunately many gardeners prefer not to grow biennials as they only flower in their second year and then disappear for ever.
Don’t you make this mistake, or you will miss out on some really beautiful plants like Foxglove, Canterbury Bells, Cotton Thistle, Echium, the list just goes on.
It’s a real shame not to grow these plants because propagating and growing them successfully is easy.
And once established they will keep self seeding giving you a continuous succession of plants and a profusion of beautiful flowers. And that is absolutely splendid.
And that of course gives you free gardening plants!
Make sure you have these plants on your plant list and grow them wherever you can in all your planting schemes.